Chlorine Sucking Flies – The Sequel

Service pros in North Central Florida are combating chlorine-depleting bugs. Are these the spiraling whitefly ... or something else?

The rugose spiraling whitefly has been blamed for a host of pool problems in southern Florida. In recent months, service pros in the north central part of the state have speculated that the critters have been creeping their way up. Turns out, it's not the whitefly that has been wreaking havoc, but the Asian woolly hackberry aphid, seen here.

Roughly five hours North of Boynton Beach, Fla. and just over a year since Pool & Spa News wrote of Palm Beach County’s newest resident, the “Chlorine Sucking Whitefly," pool service companies have begun to see the tell-tale signs of the invasive rugose spiraling whitefly in pools on their service routes. Could this tiny Central American plant destroyer have traveled 300 miles north in the past year just to wreak havoc on the swimming pools of Alachua County?

At first glance, the pool water appears as if someone had tossed handfuls of saw dust across the surface, the deck areas and patio furniture blackened with a sticky goo. The chlorine levels completely depleted, premature heavy leaf fall (it may be autumn, but it’s still 90 degrees in Gainesville), and extremely short filter runs in both residential and commercial pools, seem to match the reported M.O. of the whitefly. To be certain samples were collected from both the swimming pools and the scantily leaved host trees, which were brought to the Insect Identification office at University of Florida’s Entomology and Nematology department.

It was under the lens of a microscope that UF Biologist Lyle Buss was able to identify the small hemiptera not as the rugose spiraling whitefly, but the Asian woolly hackberry aphid. Buss went on to explain that the Aphid we were looking at was fond of sugar berry trees and has a small needle like mouth that sucks the sap from the underside of the leaves, causing them to wither and fall. He explained that the “black goo” on the deck areas was actually the sugar-rich excrement from the insect. Unaware of the effects on water chemistry, he was not surprised at the findings. He did go on to explain that the Asian woolly was in the same family as the whitefly and was first found in Florida in the late 90s.

The University of Florida reports that chemical treatment is probably not necessary for protecting the health of the trees (Halbert, Choate), but what about the pools? Natural Chemistry Regional Manager, Tom Perugini, explained that he has had great success treating South Florida pools in the aftermath of the rugose spiraling whitefly by “double dosing” the company’s Pool Perfect enzyme product with a chlorine shock chaser after 48 hours. He agreed that the treatment would only treat what is in the water now. The bugs that continued to fall and “goo” would continue to alter water chemistry and clog filtration until resolved at the source. A local pest control company, also unaware of the aphid’s effect on water balance, advised that the best treatment would involve a horticultural oil with a pesticide administered at the root of the tree in lieu of spraying to avoid pool water contamination. Unfortunately, this method is a much longer process and provides no immediate fix, but would serve as preventative measure for the next season.